1803 – Thomas Jefferson, in secret communication with Congress, sought authorization for the first official exploration by the U.S. government.

Jefferson sends secret letter to Congress, Jan. 18, 1803 On this day in 1803, President Thomas Jefferson sent a secret letter to Congress, seeking financing for a transcontinental exploration that became the Lewis and Clark expedition of 1804-1806. Jefferson sought an appropriation of $2,500, the equivalent of about $50,000 today.

Source: loc.gov